1. Field of the Invention
The present invention relates generally to the field of time-delay valves, and, more particularly, to an improved time-delay valve which is particularly suitable for use in connection with fire-fighting apparatus.
2. Description of the Prior Art
Often, a structure is subdivided into a plurality of discrete sections which may be selectively isolated from one another, and there are a myriad of different reasons for this construction.
For example, a building might be so subdivided to isolate a potentially hazardous environment. Such hazardous environment might contain combustible fluids.
Ships are another example of such structures. It is common to subdivide a ship into a plurality of compartments which may be selectively sealed from one another in the case of flooding or fire. Present ship designs often incorporate a system to flood a compartment with a suitable gas, such as CO.sub.2, to smother and suppress the fire before it spreads to other parts of the vessel.
Such fire-fighting systems generally have a suitable activation device, which may be operated as soon as a fire is observed. However, it is necessary to provide an appropriate time delay following activation, to permit personnel to evacuate the affected compartment and to permit the compartment to be sealed off. At the same time, any such time-delay device must be of reliable construction, and must be able to remain in a stand-by condition for long periods of time. Moreover, such device should be non-electrical so that the reliability of its operation does not depend on the continuity of an electrical circuit, and so that its operation does not generate an igniting spark.